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Signature Series Max-Duty Synthetic Diesel Oil 15W-40

Product code : DMEQT-EA

Outstanding extreme-pressure protection
Delivers 6X more wear protection1
Maintains proper viscosity (thickness)
Minimizes oil consumption
Maximizes fuel efficiency
Excels in extreme temperatures

1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation

Outstanding extreme-pressure protection
Delivers 6X more wear protection1
Maintains proper viscosity (thickness)
Minimizes oil consumption
Maximizes fuel efficiency
Excels in extreme temperatures

1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation

Signature Series Max-Duty Synthetic Diesel Oil 15W-40



Developed to protect the horsepower diesel enthusiasts crave and extend the life of hard-working commercial equipment in the most severe conditions. Signature Series synthetic technology delivers max-duty protection in on- and off-road applications.

See the Product Data Bulletin for full details.

MAXIMUM ENGINE PROTECTION

  • Delivers 6X more wear protection,1 delivering extra protection so you can push your diesel with peace of mind
  • Provides long-lasting wear protection, keeping cylinder liners looking like new2
  • Delivers up to 60 percent better turbo cleanliness3
  • Withstands the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower
  • Provides up to 2X better rust protection4

1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation
2Based on independent testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
3Based on specification standards of CAT C13 2nd Ring Top Land Carbon testing
4Based on industry standard testing using the NMMA FC-W Rust Test.


Delivers More Wear Protection

Third-party testing shows Signature Series Max-Duty Synthetic Diesel Oil delivers 6X more protection against wear than required by Detroit Diesel’s* standard.II

IIBased on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation.
*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.


AMSOIL Fights Wear

AMSOIL delivers powerful engine protection. How good is it? In third-party testing compared to a leading brand, AMSOIL provided long-lasting wear protection, keeping cylinder liners looking like new.DD

AMSOIL Fights Wear – AMSOIL delivers powerful engine protection. How good is it? In third-party testing compared to a leading brand, AMSOIL provided long-lasting wear protection, keeping cylinder liners looking like new.

DDBased on third-party testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.


Keeps Turbos Clean

AMSOIL Signature Series Max-Duty Synthetic Diesel Oil provides protection boosted to the max, delivering up to 60% better turbo cleanlinessJ and withstanding the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower.

JBased on specification standards of CAT C13 2nd Ring Top Land Carbon testing


Protects Against Rust

Provides up to 2X better rust protection.K Protects Against Rust – Provides up to 2X better rust protection.

KBased on industry standard testing using the NMMA FC-W Rust Test.


VISCOSITY CONTROL

  • Resists oxidation and the thickening effects of soot contamination
  • Retains viscosity after high-temperature service for maximum engine protection and efficiency
  • Provides up to 76 percent less oil consumption5

5Than required by the API CK-4 standard in the Caterpillar-1N oil consumption test


Reduces Oil Consumption

Signature Series Max-Duty Synthetic Diesel Oil provides up to 76% less oil consumption.L

Reduces Oil Consumption – Signature Series Max-Duty Synthetic Diesel Oil provides up to 76% less oil consumption.

LThan required by the API CK-4 standard in the Caterpillar-1N oil consumption test.


EXCELS IN EXTREME TEMPERATURES

  • Provides outstanding protection and performance in hot and cold temperature extremes
  • Resists thermal (heat) breakdown better than conventional and competing synthetic diesel oils.
  • Stays fluid in sub-zero temperatures for easier starting, improved oil flow and reduced wear.

See the Product Data Bulletin for full details.

Signature Series Max-Duty Synthetic Diesel Oil 15W-40



Signature Series Max-Duty Synthetic Diesel Oil 15W-40

  • 5
    Signature Series 5w-40 Diesel OIl
    By  BEN,  a  Verified Buyer  from  Tulsa  on  September 16, 2021

    Describe the issue

    Been using this oil in my 2019 Ford F350 Super Duty Lariat with the 6.7L Powerstroke Diesel engine and so far so good. Engine runs clean and smooth with zero issues. This is really good oil.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    AMSOIL DIESEL OIL
    By  ROBERT,  a  Verified Buyer  from  GEORGIA  on  September 15, 2021

    Describe the issue

    Pulling a 15k # boat, you want to have the best protection you can give your engine! This is the best you can get!
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great Product
    By  CHRISTOPHER,  a  Verified Buyer  from  Missouri  on  September 15, 2021

    Describe the issue

    I run my duramax quite hard and have for many years. This oil in my mind is the best. I’ve had no issues internally and even more surprising I have noticed the oil to be less dark on change intervals than other brands which is incredible for a diesel in and of itself.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Duramax
    By  DARYL,  a  Verified Buyer  on  September 13, 2021

    Describe the issue

    Excellent
    Bottom Line
    Yes, I would recommend this to a friend.
  • 2
    MAX -DUTY
    By  JACK,  a  Verified Buyer  from  PEORIA IL  on  September 07, 2021

    Describe the issue

    OIL SEEM TO BE WORKING FINE ONLY BEEN IN THE TRUCK FOR 200 MILES
  • 5
    Outstanding!
    By  RICHARD,  a  Verified Buyer  on  September 07, 2021

    Describe the issue

    Highly recommend!
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Diesel Oil
    By  DAVID,  a  Verified Buyer  on  September 07, 2021

    Describe the issue

    Best oil out there, especially for extreme conditions
    Bottom Line
    Yes, I would recommend this to a friend.
  • 2
    Good oil
    By  WAYNE,  a  Verified Buyer  from  Chilliwack   on  September 06, 2021

    Describe the issue

    It’s great oil. Just did my last oil change and I think it will be the last. As it is already expensive and they increase the price , and made me pay for shipping. That was the last purchase.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Best Diesel oil
    By  Beardedcajun,  a  Verified Buyer  from  Texas  on  September 05, 2021

    Describe the issue

    I love the Diesel oil, as I love Amsoil period, very high quality oil, I use their oils in all my trucks, tractors, zero turn, and side x side.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    oil review
    By  CHARLES,  a  Verified Buyer  on  September 05, 2021

    Describe the issue

    great oil